With the rapid progress of display technology, the display device with touch function has been more and more popular because of its advantages such as visualized operation. Based on the relative position of the touch panel and the display panel, the existing display device with touch function mainly comprises the on cell type touch panel and the in cell type touch panel.
FIG. 1 shows a schematic diagram of a color film substrate in a typical on cell type touch panel in the prior art. The color film substrate comprises a basal substrate 1, a colorful film layer 2 formed on the lower surface of the basal substrate 1, and a touch electrode wire pattern 3 formed on the upper surface of the basal substrate 1. In the practical application, the touch electrode wire pattern 3 is typically manufactured with ITO material, of which the refractive index is 2. For this reason, the light passing through the ITO material will be shifted to the left, while the light without passing through the ITO material will be refracted directly, and will not be shifted to the left. Therefore, for the right region of the touch electrode wire pattern 3, the light passing through this region should be shifted to the left, while the light passing through the right periphery of this region should not be shifted to the left since it does not pass through the touch electrode wire pattern 3, thereby causing light loss in this region, forming a dark area as shown in the figure. Accordingly, the light passing through the left periphery of the left region of the touch electrode wire pattern 3 will not be shifted to the left, and will overlap with the light shifted to this position due to the touch electrode wire pattern 3, forming a bright area as shown in the figure. This will cause a brightness difference line in the display image.